1. Field of the Invention
The invention relates to a latching device for a folding roof of a motor vehicle with a latch hook which is movably supported on the free end of the folding roof and which can be latched by a drive means in lock engagement on the airscoop of the motor vehicle. Furthermore, the invention also relates to a latching device for latching the folding roof of a motor vehicle on an airscoop which has a movably supported latch hook which can be latched by a drive means in lock engagement on the counterpiece of the lock.
2. Description of Related Art
German Utility Model DE 297 03 774 U1 discloses a closing device for a convertible folding roof which has a lock hook which is supported on the roof free end of a convertible to be able to pivot around the transverse axis of the motor vehicle and which can be swung by means of a four-bar mechanism which is actuated via a handle into its locked position in which it keeps the roof free end of the convertible folding roof on the apron closed and latched.
Published International Application WO 92/15466 (published European Application EP 0 536 354 and corresponding U.S. Pat. No. 5,154,479) discloses a latching device for a folding roof which has a lock hook which is pivotally mounted on a bearing lever. The bearing lever is pivotally mounted on the bearing plate of the free end of the folding roof and can be moved by a motor via a drive part. The bearing plate has a guide surface against which the lock hook is tensioned by means of a spring. By means of the movable drive part the lock hook is moved into the engagement and locking position on an abutment on the apron by means of the bearing plate and the guide surface out of its disengaged position.
Published European Patent Application EP 0 492 006 A1 and corresponding U.S. Pat. No. 5,269,586, discloses a device for lowering and holding the free end of a motor vehicle folding roof. A lowering and latch hook is movably supported on the frame on the bottom of the apron for engaging the abutment on the roof free end. The lowering hook has an elongated guide slot through which a frame-mounted guide journal extends. On the back end of the lowering hook, a pivot pin is attached which is guided in the receiving slot of the frame and which can be moved by a drive means. The driven pivot pin which is moved in the receiving slot pivots the lowering hook around the frame-mounted guide journal while at the same time the lowering hook is pushed relative to the guide journal.
The primary object of the present invention is to devise a latching device as described initially which, with a simple structure, ensures reliable lowering of the free end of the roof on the last path of motion to the apron and the latching thereto.
This object is achieved in a first latching device in accordance with the invention in that the latch hook for closing and latching the folding top can be moved in a pivoting and sliding motion relative to the guide part of the roof free end which is guided into engagement with the guideway of the latch hook, and can be pivoted around the guide part. Relative to a circular-arc shaped pivoting motion around a fixed axis of rotation, by means of the additional displacement of the latch hook relative to the roof free end the desired dynamic behavior can be set, in which the roof free end traverses different paths in the lengthwise direction of the motor vehicle and in the vertical direction (x-direction and z-direction) on the last path of motion upon approaching the apron and when closing and latching the folding roof on the apron. Thus, the high tension forces which are necessary to close the folding roof and which are necessary on the last path of motion to tension the roof cover and to press the roof free end against a seal can be provided by a transfer of motion from a comparatively weak drive motor or the like and also during manual actuation. In order to guide the roof free end reliably to the apron in the last path of motion, the latch hook can be made elongated and can be moved over a correspondingly large displacement path in the respective displacement direction. The latch hook is then preferably located on the roof free end in a pivot plane which is aligned especially roughly in the vertical lengthwise plane of the motor vehicle.
Preferably, the drive means moves an intermediate element and especially a pivot lever which is coupled to the latch hook and moves it for closing and latching the folding roof in a pivoting and sliding motion relative to the stationary guide part which engages by guidance the guideway of the latch hook as, for example, a guide, and pivots around the guide part. By means of the intermediate element or the pivot lever, advantageously, a certain dynamic behavior of the latch hook can be fixed and adjusted in addition to the dynamic behavior which is provided by the drive means. The pivot lever is feasibly supported parallel to the latch hook, and the support can be a pivot axle with an arrangement relative to the guide part of the latch hook which determines the dynamic behavior. The pivot lever furthermore enables the actuation speed and the actuation path of the drive means to be easily reduced or raised. The guideway of the latch hook is feasibly an elongated recess in the form of a guide slot for the pin or for the roller which is being supported on the pin.
The object is also achieved in that, in a second latching device according to the invention, the latch hook is movably supported either on the free end of the folding roof or on the apron and can be latched on the apron or the roof free end as a lock counterpiece, and in that the drive means moves an intermediate element, and especially a pivot lever, which is coupled to the latch hook, and to close and latch the folding roof, moves the hook in a sliding and pivoting motion relative to the stationary guide part which is guided into engagement with the guideway of the latch hook and pivots the guide part. The latch hook, and thus also the drive means, can accordingly be housed both on the apron and also on the roof free end corresponding to the available space requirement. The interposed intermediate element or the pivot lever offers the aforementioned advantages.
One preferred embodiment calls for the latch hook to be coupled to the drive means via a latching mechanism which contains the pivot lever which is pivotally mounted on the roof free end or the apron and which is connected to the latch hook via a coupling element which is spaced apart from the guideway, for example, a pin, and for the latching mechanism to slowly move the latch hook in the last section of movement before its latching position on the apron at an increased drive force.
Feasibly, the coupling element and the pin are guided by the pivot lever on a curved path, especially on a section of a curved path. The curved path determines the respective distance from the pin to the stationary guide part or the guide slot of the latch hook. A curved path in the form of an orbit is formed when the pivot lever is supported to be able to pivot around a fixed pivot axis. When the pivot axis is located adjacent to the stationary guide part, with the corresponding direction of motion, the desired increasing distance results between the pin and the guide part which causes displacement of the latch hook in the desired manner.
Preferably, the drive means contains a drive journal which is coupled to the pivot lever and drives it in two opposite directions for latching or unlatching, the drive journal, on an essentially linear path which is spaced from the pivot axis or the bearing pin of the pivot lever, being moved past the pivot axis or the bearing pin and being movably held in the guideway of the pivot lever to equalize the changing distance to the pivot axis in drive engagement. However, the drive means can also drive the drive journal on a nonlinear path which is laid out according to the required dynamic behavior.
For reliable closing of the folding roof, especially for motion into the seal, it is a good idea if the drive journal is moved slowly by the drive means against the latching position of the latch hook. The slowed motion can be achieved, for example, by a variable speed of the drive motor. One preferred embodiment, however, calls for the drive means to have a drive rod which is located on the free end of roof or the apron in the transverse direction and which has a drive journal on its outer end which fits into the latching mechanism and is pivotally mounted on the opposite, inner end so that the drive journal is guided on a roughly linear path of motion when the drive rod is pivoted, and a guide element which intersects the drive rod at an acute angle and which is securely mounted on the roof free end, or on the apron, in the transverse direction and on which there is movably supported a guide block which can be driven by a drive unit and which fits into a lengthwise guide of the drive rod by sliding at the intersection point, and by means of its lengthwise displacement on the guide element, pivots the drive rod with the drive journal. By means of this simple mechanical mechanism, the dynamic behavior of the drive journal can be adjusted without special rpm control of, for example, an electric drive motor used for that purpose. Thus, the guide block which is driven with a roughly constant speed, accelerates or slows down the journal depending on its direction of motion.
If the guideway or the guide slot in the latch hook has at least one nonlinear path section, superimposed on the motion of the intermediate lever or the pivot lever, the motion of the latch hook can also be adjusted.
Preferably, the latch hook in the latch mechanism is movably supported in a symmetrical arrangement between two holding plates and two pivot levers. Thus, the latch hook is accommodated, for example, between two holding plates which are mounted on the roof free end and is moved by two pivot levers which are each pivotally mounted on the holding plate.
Feasibly, the drive means comprises an electric motor which drives an actuating cable which is connected to the guide block via a pinion. However, hydraulic drives can also be used. Alternatively, the propulsion means can be a handle, a turning handle, which is connected to the guide block via a raising cable to move it. Two latching mechanisms which are spaced apart as well as only one latching mechanism can be actuated by the central arrangement of the drive means.
In one alternative preferred embodiment, the drive means is formed as a pivoting handle for each latching mechanism which is coupled to the journal in a drive connection. The handle can be latched in the closed position by a safety device against unwanted opening.